The Queen makes an appearance before the fight with Mergo's Wet Nurse. She is seen weeping. Given what is revealed during the fight, that the child was somehow killed, it can be assumed that this child is the offspring of the Queen.
The Third Umbilical Cord that you receive from the fight with the Wet Nurse was bestowed upon the Queen by the Great Ones. This prophecy is found within Byrgenwerth on a bookshelf. In short: "… And when the Great Ones descend, a womb will be blessed with child."
We see the Queen in a cutscene after defeating Rom, the Vacuous Spider. We see a blood red moon, and start to hear the cries of a young child from this point on.